Apparatus for reducing heat transfer



March 29, 1966 A. SHERMAN 3,242,982

APPARATUS FOR REDUCING HEAT TRANSFER Filed Aug. 20, 1964 Cool 01/6 2 FLl/lo Fig-1 INVENTOR 19/? 77/01? 51/89/719 BY 4770,? y

United States Patent 3 242 982 APPARATUS FOR REDUEIING HEAT TRANSFER Arthur Sherman, Norristown, Pa., assignor to the United States of America as represented by the Secretary of the Air Force Filed Aug. 20, 1964, Ser. No. 391,055 1 Claim. (Cl. 165-134) This invention relates to an apparatus for reducing the heat transfer from a hot electrically conducting fluid, such as an ionized gas, to a solid surface.

One object of the invention is to provide a device for reducing the heat transfer to a solid surface such as the outer surface of a high velocity vehicle from the ionized gas through which the vehicle passes in flight.

Another object of the invention is to provide a method for reducing the heat transfer to a surface from an electrically conducting fluid by the use of a magnetic field to separate the conducting fluid from the surface and by introducing a coolant such as a gas or liquid into the separated region.

These and other objects will be more fully understood from the following description taken with the drawing, wherein:

FIG. 1 shows a sectional view of a device for reducing the heat transfer to a surface according to one embodiment of the invention; and

FIG. 2 shows a modification of the device of FIG. 1 according to another embodiment of the invention.

When an electrically conducting fluid is passing a wall or surface such as the ionized layer around a spacecraft on re-entry or an ionized stream in a nozzle, it is possible, according to this invention, to reduce the heat transfer to the surface by providing a localized magnetic field adjacent the surface to cause separation of the conducting gas from the surface and by injecting a cooling fluid into the separated region. The separation of the conducting fluid from the surface and the injection of cooling fluid into the separation co-opera-te to reduce the heat transfer to the surface.

Referring more particularly to FIG. 1 of the drawing there is shown a surface of a portion of a wall 11, of non-magnetic material, such as the wall of a space vehicle. A permanent magnet 12 is located in the wall 11 and has its poles projecting toward the surface 10 and has the south pole located in the direction of travel of the conducting fluid with respect to the north pole. The charged particles in the conducting fluid will tend to follow the magnetic lines of force to provide a separation region 13 between the conducting fluid and the surface 10. A

cooling fluid such as super-cooled air, indicated by the Patented Mar. 29, 1966 "ice arrow 16 is injected into the region 13 from a cooling fluid supply 17 through tube 18.

While only one magnet and cooling fluid supply tube is shown it is obvious that many such systems would be needed over the surface of a space vehicle. Also it is obvious that certain areas of a space vehicle might not require such a system in which case they would be omitted from these regions. This invention however relates to the particular system for reducing heat transfer and not to the particular location or use of the system.

While a permanent magnet is shown, it is to be understood that the magnetic field could also be provided by the use of conductors located within the wall as shown in FIG. 2 wherein a plurality of wires 21 are imbedded within the wall 11. The cooling fluid would be supplied through cooling tube 18 in the same manner as in FIG. 1.

There is thus provided a device for reducing heat transfer to a surface from an electrically conducting fluid passing the surface.

While certain specific embodiments have been described it is obvious that numerous changes may be made without departing from the general principles and scope of the invention.

I claim:

Apparatus for use in a flight vehicle adapted to travel through space at a sufiiciently high velocity that a hot electrically conducting fluid flowing past the outer surface of said vehicle is produced, the combination of means adapted to be carried by said vehicle for producing a mag netic field having flux lines that project from said surface and extend substantially in the direction of the flow of said flu-id in at least one discrete location along said surface to thereby provide a separation region at said location between said conducting fluid and said surface, said separation region being located rearward of a non-separated region whereat said fluid and said surface are in relatively close relationship, and means positioned at said separation region only for injecting a cooling fluid into said separation region between said conducting fluid and said surface, whereby the heat transfer between said conducting fluid and said surface at said separation region is reduced to a minimum.

References Cited by the Examiner UNITED STATES PATENTS 2,468,820 5/1949 Goddard 102 92.5

3,162,398 1 2/ 1964 Clauser et al. 24414 FREDERICK L. MATTESON JR., Primary Examiner.

ROBERT A. OLEARY, Examiner.

A. W. DAVIS, Assistant Examiner. 

